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This study was to examine the efficiency of native microorganisms, in relation to the commercial bacterium Clostridium thermocellum ATCC 27405 for bioethanol production from waste watermelon on a pilot scale. The raw material was subjected to a grinding process for the later stage of hydrolysis under different temperatures using Aspergillus fumigatus and Leuconostoc dextranicum native microorganisms. This was followed by fermentation using control strains of Zymomonas mobilis (native microorganism) and C. thermocellum ATCC 27405. After hydrolysis, the fermentation product was evaluated by physico chemical analysis, pH determination and reducing sugars concentration using refractometry. Finally, the product obtained was subjected to vacuum distillation to increase the grade of purity. It was there after analyzed using pycnometry and gas chromatography (GC). GC results revealed that the yield of ethanol from hydrolysis and fermentation by native strains was improved by 27.62%, compared to yields of ethanol obtained from Z. mobilis (11.62%) and C. thermocellum (3.10%). It was therefore concluded that the native strains were more efficient in hydrolysing and fermenting watermelon compared to the commercial C. thermocellum and Z. mobilis. Key words: Aspergillus niger, Clostridium thermocellum ATCC 27405, Zymomonas mobilis, hydrolysis, fermentation processes.

Indiscriminate use of insecticides and fungicides leads to a combined contamination of pesticide residues in the soil environment and causes a severe threat to beneficial microbial activities. Hence, it is essential to assess the microbial populations of soils in the biosphere. In this study, two insecticides, cypermethrin and chlorpyrifos alone and in combination with two fungicides, mancozeb and carbendazim, were assessed for their effects on the bacterial and fungal populations in two tomato cultivated soils. Samples of soil-1 and soil-2 were collected from tomato cultivated fields of El Quienchi, Pichincha, Ecuador. Initially the physico-chemical characteristics of soils, e.g., soil pH, organic matter, total nitrogen, electrical conductivity, sand, silt and clay contents were detected, and then soil bacterial and fungal populations were determined. The influence of selected pesticides alone or in combination on the bacterial and fungal population was concentration-dependent; the populations were increased with increasing concentration of pesticides up to 5.0 kg ha−1 compared to the controls in 10-day incubated soils. The bacterial and fungal populations continued to increase up to 20 days, and then, gradually decreased after 30 and 40 days of incubation. The results clearly indicate that application of individual and/or mixtures of the pesticides in cultivation of tomato, at field application rates (2.5–5.0 kg ha−1), significantly improved the bacterial and fungal populations in soil-1 and soil-2. However, further increase in the dose of pesticides (7.5–10 kg ha−1) dramatically decreased the bacterial and fungal populations. On the other hand, insecticides in combination with fungicides showed negative effect on fungal populations.

Ecuador generates lots of lingo cellulosic organic waste from cocoa, rice and corn agribusiness, and these products are rich in cellulose and can be used in fermentation processes by enzyme producing yeasts. In this study, the phytopathogenic fungus Moniliophthora roreri was isolated, characterized and the kinetics of production of cellulose was studied using rice husks, cocoa shell and cob as a growth inducer substance for a period of 20 days. The carboxymethylcellulose (CMC) was used as specific substrate to evaluate the kinetic parameters of the enzyme at different concentration of 0.5%, 1% and 1.5%; to evaluate the Vmax, Km, specific activity, kcatwe worked with the Michaelis-Menten and Lineweaver-Burk linearization and the crude enzyme was purified with ammonium sulfate. The enzyme production was increased on 10th, 15th and 20th day in rice hulls, cocoa husk and cob, respectively. There was also an increased enzyme activity and the kinetic parameters obtained from rice husk. The purification is a step to increase the specific activity of the enzyme in each of the extracts is under study.

The effect of the co-inoculation of arbuscular mycorrhizal fungi (AMF) and Azospirillum on micro-propagated banana seedlings development during their adaptation phase was determined. At the time of transplanting, banana seedlings were inoculated with an indigenous mycorrhizal inoculum containing 10 spores/g at four doses: 0, 50, 100 and 200 g. Seventy days after fungal inoculation, 20 ml of Azospirillum in four concentrations (0, 106, 107 and 108 CFU/ml) were applied. Finally, after 98 days from the start of the experiment a second dose (40 ml) of Azospirillum in the concentrations mentioned above was inoculated. Plants were harvested 5 months after transplanting and the growth and nutritional parameters were evaluated. The analysis of the data showed that banana plants co-inoculated with 200 g of AMF and 1.5E8 CFU/ml of Azospirillum presented greater development, an increase of 7 times in height, 4 times in perimeter, 16 times in leaf area, 12 times in aerial biomass, and 8 times in root biomass en relacion a las plantas control. The results achieved were due to synergism between fungus-bacteria when inoculated at higher doses, with lower doses stimulating growth is minimal. The co-inoculation in high doses demonstrates adequate support and cooperative effect between HMA and Azospirillum crops. In addition, co-inoculation promotes optimal nutritional status because microorganisms allowed plants achieve greater absorption of phosphorus and nitrogen relative to those treated with single inoculation and the control.sphorus and nitrogen relative to those treated with single inoculation and the control.

1 Department of Life Sciences, Universidad de las Fuerzas Armadas-ESPE, SangolquiPOBOX: 171-5-231B, Quito, Ecuador, South America. 2 Faculty of Prometeo Project, SENESCYT, Quito, Ecuador. 3 Shenzhen Key Laboratory of Advanced Materials, Department of Materials Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen – 518055, China. 4 Department of Environmental Engineering, Universidad Estatal Amazonica, Puyo, Ecuador. 5 Loyola ICAM College of Engineering and Technology (LICET), Loyola campus, Chennai-600034, India.

1 Department of Life Sciences, Universidad de las Fuerzas Armadas-ESPE, SangolquiPOBOX: 171-5-231B, Quito, Ecuador, South America. 2 Department of Biotechnology, Universidad de las Americas UDLA, Quito, Ecuador. 3 Department of Zoology, University of Pune, Pune, India. 4 Department of Environmental Engineering, Universidad Estatal Amazonica, Puyo, Ecuador. 5 Loyola ICAM College of Engineering and Technology (LICET), Loyola campus, Chennai, India.

The objective of this study was to determine the effect of application of pesticides on morphology, viability, and germination of pollen grains of Blackberry (Rubus glaucus Benth.) and Tree tomato (Solanum betaceum Cav.). The study was performed at Patate, Tungurahua province, Ecuador and was divided into two phases. Phase one dedicated to the study of morphology, viability, and identification of nutrient solution for better germination of pollen grains and phase two for the analysis of the effect of conventional, organic, and biological pesticides on pollen grain germination and pollen tube length. To study pollen morphology, pollens were extracted by hand pressure and was analyzed by optical and electron microscopy. The viable pollen grains were identified by staining with 1% acetocarmine. Even though Tree tomato and Blackberry pollen grains are morphologically similar, their exine shapes differ. We observed four times increase in pollen germination rate when suspended in nutrient solution (Sucrose with Boric acid) than control (water). Pollen grains under nutrient solution were subjected to different groups of pesticides for the period of 2, 4, and 6 h. With respect to pesticide affect, the Blackberry pollen grain germination followed the following order: Lecaniceb > Beauveb > Metazeb => Myceb > Control. However, the effect on Tree tomato pollen grains was as follows: Lecaniceb > Myceb > Cantus > Bacillus thuringiensis > Kripton > Control. As per as pollen grain germination is concerned, we observed that the chemical pesticides are more harmful than other pesticides. So, it is necessary to perform screening test for different pesticides and their effect on pollen grain germination before applying to the fields.

The objective of this study was to determine the effects of two insecticides, namely, acetamiprid and carbofuran on the enzymatic activities of arylamidase (as glucose formed from sinigrin) and myrosinase (as β-naphthylamine formed from L-leucine β-naphthylamide) in the black and red clay soils collected from a fallow groundnut (Arachis hypogaea L.) fields in the Anantapur District, Andhra Pradesh, India. The study was realized within the framework of the laboratory experiments in which the acetamiprid and carbofuran were applied to the soils at different doses (1.0, 2.5, 5.0, 7.5, 10.0 kg ha(-1)). Initially, the physicochechemical properties of the soil samples were analyzed. After 10 days of pesticide application, the soil samples were analyzed for the enzyme activities. Acetamiprid and carbofuran stimulated the arylamidase and myrosinase activities at lower concentrations after 10 days incubation. Striking stimulation in soil enzyme activities was noticed at 2.5 kg ha(-1), persists for 20 days in both the soils. Overall, higher concentrations (5.0-10.0 kg ha(-1)) of acetamiprid and carbofuran were toxic or innocuous to the arylamidase and myrosinase activities. Nevertheless, the outcomes of the present study clearly indicate that the use of these insecticides (at field application rates) in the groundnut fields (black and red clay soils) stimulated the enzyme (arylamidase and myrosinase) activities.

The release of heavy metals in to the aquatic environment causes water pollution problems because of their toxicity, persistence and bioaccumulation. Lead has no known role to play in the human body that is physiologically relevant, and its harmful effects are myriad. Lead from the atmosphere and soil ends up in water bodies thus affecting the aquatic organisms. This situation has thus prompted numerous investigators to study on the effects of this heavy metal on the biological functions of aquatic organisms, particularly on the antioxidant enzyme activity in fish. In the present investigation the effect of lead acetate (heavy metal) on antioxidant enzyme activity was evaluated in the fresh water fish Labeo rohita. The experimental fish were treated with sub lethal concentration of lead acetate (0.015 mg/ L) for 120 hrs. Spirulina was used as supplementary feed during the experimental period. We observed various lead induced lipid peroxidation (LPO), antioxidant enzyme (SOD and CAT) changes and Spirulina supplementary feed therapeutic efficiency was observed in the gill and liver tissues of the fish. All the experimental data are statistically significant at p